fix: enhance hero description for Azure Copilot CLI experience

Author: jongio

web/src/pages/index.astro

@@ -111,9 +111,9 @@ const stats = [
         </h1>
 
         <p class="hero-description animate-fade-up" style="animation-delay: 0.2s">
-          Start an immersive Azure Copilot CLI experience. Just describe your scenario
-          and Copilot — with deep knowledge of all things Azure — will help you
-          build an amazing solution.
+          Welcome to an immersive Azure dev experience with Azure Copilot CLI. Just describe your scenario
+          and Copilot - with deep knowledge of all things Azure - will help you
+          build and deploy an expertly-vetted Azure solution.
         </p>
 
         <!-- Front and center: azd copilot -->